Electric-fuse connection and terminal contact



April 2, 1929. so 1,707,327

ELECTRIC FUSE CONNECTION AND TERMINAL CONTACT Filed March 30, 1926 fnv e Minesge 1Z0 {go/fermion- Patented Apr. 2, 1929.

UNITED STATES MAX SOFERMAN, OF PHILADELPHIA, PENNSYLVANIA.

ELECTRIC-FUSE CONNECTION AND TERMINAL CONTACT.

Application filed March 30, 1926. Serial No. 98,504.

In the manufacture of electric fuse plugs it has usually been the custom to insert the fuse wire and solder it to the end terminal contact and to the electric current conducting metallic screw threaded shell or sleeve. This method of procedure is tedius and expensive, often resulting in insecure connections rendering the plugs of no value. In View of the above mentioned method of construction, numerous devi es have been invented to facilitate the production of electric fuse plugs. Some of said devices have included attaching means for fuse Wire inserted in the end of the fuse plug body. None of said devices has been entirely satisfactory in securely retaining the fuse wire and insuring proper contact with the screw threaded shell and central contact under all conditions.

One object of my invention is to provide an improved construction which will facilitate and reduce the cost of manufacture of electric fuse plugs or like structures and at the same timeinsure good and permanent contacts to properly conduct the electric current.

Another object is to so construct and apply my invention that it is unnecessary to use solder in order to effect proper connec tion of the parts.

These objects and other advantageous ends which will be set forth hereinafter, I attain in the following manner, reference being had to the accompanying drawing in which Figure 1 is a central longitudinal sectional elevation of a fuse plug having my invention applied thereto, g

Figure 2 is an elevational side view of said plug with certain ,of'the parts removed,

Figure 3 is a bottom view of said plug with the metallic screw threaded shell removed, 7

Figure 4: is a section taken on the line L- L of Figure 1, I

Figure 5 is a fragmentary bottom plan view showing the shape of the aperture in the lower end of the'plug' body,

Figure 6 is a perspective view showing certain of the arts assembled and ready to be inserted wit in a fuse plug body, and

Figure 7 is a rear elevational view of a part of my invention as shown in Figure 6.

Referring to the drawing, 7 represents a fuse plug body which is made of porcelain I or other suitable insulating material, said body having a chamber 8 which leads downwardly from its top as shown in Figure 1, the bottom or base 9 of said body having a hole or aperture 10 extending upwardly from its lower face and communicating with the chamber 8. The aperture 10 is substantially rectangular and has an off-set notch 11 as clearly shown in Figures 4 and 5, said off-set notch preferably being located centrally between the two side walls 12 and 13 of the aperture 10 for a purpose hereinafter described. 7 a

The body 7 has two outer annular ledges or shoulders 14: and 15 both of which face downwardly and are of different diameters. The body 7, between the ledges 14 and 15, has formed thereon a screw thread 16 upon which is screwed a metallic screw threaded sleeve 17, the outer screw threads of said sleeve 17 serving to allow the fuse plug to be inserted, within any receptacle into which it is desired to place the fuse plug in the usual manner of inserting fuse plugs.

The body 7 has a channel 18 which, at its top, communicates with the chamber 8 and at its lower end, communicates with a groove 19 formed in the outer face of the body 7. The groove 19 extends downward to' the ledge 15 and includes an angular deflecting surface portion 20 at a position below the ledge 14 as shown in Figure 1, said deflecting surface portion 20 being for a purpose hereinafter described.

A unitary terminal contact clamp 21, which is made of a single piece of sheet metal, is split and pressed to produce the following structure. A transversely extending arm portion 22 has, depending therefrom, a central tongue 23 which is bent in the direction of its length in the form of a compound or ogee curve to produce an in wardly bulged portion 24. l The lower end of the tongue 23 merges into a plate portion 25. Two lateral fingers 26 and 27 depend from the arm 22 at opposite sides of the tongue 23 and are bulged or curved inwardly to a greater extent than the portion 24: of the tongue 23 so that the free end portions 28 and 29 of said fingers 26 and 27 extend directly over the top surface of the plate 25. Projecting upwardly from the arm 22 is a split binding cuff 30 adapted to embrace and firmly squeeze and clamp one end portion of an elongated fuse strip 31.

A. second unitary terminal contact clamp 32, which is made of a single piece of sheet.

metal, is split'a-nd pressed to produce the following structure. A Contact flange foot has two oppositely ezicending lateral. i l portions 34 which preferably extend upwardly at a slant to the central portion 2-535 as clearly shown in Figures 2 and (3. 6 li binding cull 36 extends upwardly from the central portion and this binding cull 3o embraces and squeezes the opposite end portion of the :luse strip 31 so as to nrnily clai'up the same.

riny suitable top closure can provided for the fuse plug and in the present instance, I have shm a disk 3'? Wlllcll may be made of mice with a surrounding; cap ring 38.

In assembling the structure, considering that the sleeve 17 and top closur' structure are not connecterfl to the fuse plug body, the fusestrip 81' with the clamps 21 and connected thereto is applied 1 the tellow-ring; manner. The device 3.1 it)" i -;e; 'teil upwardly through the aperture o the chamber 8, the wide port on of s 10 being sullici-ont to allow the tool. le) freely passthercthrough. The l'uscstrip is sul'iiciently still to support the dc so that a \Ollilntli. can easily and (llliciiij v' push the device 32 upwardly through. the chamber 8' to such ext at that he can then grasp the device 32 from the top of the chan'iber and pull or drag the device 2i in "i the cult 30passes through the apertu The workman can then guide and put arm 22 into the aperture 10 with the tougur within the ell-set notch ii, the side edg' the lingers'26 and 27 engaging the walls 12 and 13 of the aperture while the outer a: aperture sligit and Hex saic. lingers 26 an d 27. i will also causethe rear face ll) of the tongue 23 to contact with thewall ll of the notch 11 at ditl'erent points within the length of he bulged portion 24: as clearly shown in l1 1;;- ure 1, and the plate 25 will abut the bottom surface of the base 9 and overlap the aper ture 10 as clearly shown in Figures 1, 3 and 4. Also by the couettruction, including the bulged portion 25% of the tongue a part of said tongue will overlap the surface which forms the bottom of the chamber 8, said overlapping being" shown at 43 in Figure 1, the cult 3O occupying a postion against the side wall tl of said chamber 8. In this manner the device 21 is secured against accidental displacement and the plate 25 will serve as an electric cont-act plate when the ruse plug is inserted in a receptacle in the usual manner. I preferably slightly slant the plate 25 relatively to the bottom surface of the base 9 as shown in Figure 1, with the lower ends of the 26 and 2-7 abutting or nearly abutting the top surface oi? the plate so that a slight resiliency is given to the plate 25, with a resistance produced by the resilient fingers 26 and 27, so as to insure a good electrical contact when the fuse plug is inserted within a receptacle.

fisher the devi'e 21 has beer iir'er'ed as a ore des r bod, the workman then bends the fuse strip ill and pushes the device 2-32 downwardly thrmigh the channel l8. Durightly oil-set to the cult $136 which cull 36 to remain in the groove e cxtrune ends oi? the portion 3; in 15 as clearly shmvu in the sleeve until the lower interned flange oi said sleeve abuts and compress s the foot e?) thereby holding the itoot Z133 tirinly :zp' inst the ledgzic l5. itherniore N we internal diameter of the sleeve 1? is preferably such as to cause Ty t with the cull 36 adjacent the sp t 1 r I.- .i c cm ws lQrU u" uy hold saideui, on, liltras been applied as just decribeth ens ot the flange l?) may be pressed upwardly into notches 47 in the shoulder 15 to guard against acciuental rotation ot the sleeve 17 relatively to the body 7. The top closure can then be applied and the plug is ready for use.

It has bee; found that the fuse with the devices 21 and 32-can be attached in a "few seconds without requiring the soldering oi? any 0" the parts.

Furthermore, by having the tongue 23 located within the notch 11 with the fingers 26 and 27 abutting the walls 12 13 and 39, a structure is produced free from detrimental vibration and accidental dislodguient and not only is there a general three point contact produced. by the portions 23, 26 and 27 but there'is an overlap present such as the overlap oil the part 43, which renders the attachment additionally secure.

Having thus described inyinvontion what I claim as new and desire to securebyLettors Patent is:

1. In a i" so holder, a body structure having' an aperture; and a fuse connecting device having lingers arranged in different lateral flexing planes and bearing upon the wall of said aperture to hold saiddevice rel atively to said body structure.

2. In a fuse holder a fuse; a body structure having an aperture; and a fuse connecting; device having a split portion providing parts bent in opposite directions to resiliently bear upon portionso'li the wall of said aperture, said device having a split Flu fuse binding cuff around said fuse at a position remote from the flexing zone of said resiliently bearing parts.

3. In a fuse holder, a body structurehaving an aperture; and a fuse connecting device having portions including fingers-arranged in different lateral flexing planes and bearing upon the wall of said aperture to hold said device relatively to said body structure, one of said portions being extended to provide a contact plate outside of said body structure.

4. In a fuse holder, a body structure having an aperture; and a fuse connecting de-' vice having portions arranged in different flexing planes and bearing upon the wall of said aperture to hold said device relatively to said body structure, one of said portions being extended to provide a contact plate outside of said body structure, the other portion terminating adjacent said plate at a position remote from the junction of said first portion with the plate to provide a resilient backing for the plate.

5. In a fuse holder, a fuse; a body structure having an aperture; and a fuse connecting device having a split portion including a tongue terminating in a contact plate and fingers at opposite sides of said tongue,

said fingers and tongue being bent to bear upon the wall of said aperture, said device at a position remote from said split portion I having a cuff in clamping contact with said fuse.

6. In a fuse holder, a body structure having an outer ledge and a channel leading to the outside thereof; a fuse; a fuse contact clamp secured to said fuse and adapted to be projected through said channel to the outside of said body structure, said device having a foot portion with a resilient part adapted to engage said ledge; an electric contact member connected to the outside of said'body structure and adapted to hold said resilient part of said foot against said ledge; and an outer contacting shell adapted to press said foot against the ledge.

7. Ina fuse holder, a fuse; a body structure having an aperture with an off-set notch within the width thereof; and a fuse connecting device having a split portion including a tongue terminating in a contact plate and fingers at opposite sides of said tongue, said tongue being located within said off-set notch, said fingers and tongue being bent to bear upon opposite portions of the wall of said aperture, said device being secured to said fuse.

In testimony whereof, I have signed my name to this specification.

MAX SOFERMAN. 

